Dynamo



E. A. WATSON.

DYNAMO.

APPLICATION FILED MAR. 31' 192 0.

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0 0 0 0 00000 0; 00 0009 'h'vvrovw E. A. WATSON.

DYNAMO.

APPLICATION FILED MAR. 31, 1920.

1,375,192. Patented Apr. 19, 1921.

4 SHEETS-SHEET 2.

L211 912201 @4110?? 012/ 15 %/MM E. A. WATSON.

DYNAMO.

APPLICATION FILED MAR. 31. I920.

1,375,192. Patented Apr. 19, 1921.

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iwozzwy E. A. WATSON.

DYNAMO.

APPLICATION FILED MAR. 31, 1920.

1,375, 192. Patented Apr 19, 1921.

4 SHEETS-SHEET 4.

UNITED STATES PATENT OFFICE.

' ERNESTANSLEY WATSON, OF COVENTRY, ENGLAND, ASSIGNOE TO THE C. L. I.

MANUFACTURING COMPANY LEMITE'D, OF BIRMINGHAM, ENGLAND.

LDYNAIVIO.

T 0 all whom it may concern:

Be it known that I, ERNEST rlNsLnY War son, a subject of the King of Great Britain and Ireland, residing at Victoria Works, est Orchard, Coventry, in the county of Warwick, England, have invented certain new and useful Improvements Relating to Dynamos of which the following is a specification.

This invention has for its object to construct an improved dynamo for providing current for the lighting, ignition and other equipment of motor road vehicles, the generator being of the type comprising a permanent magnet, a shuttle type armature and a two part commutator.

The invention is especially useful for small dynamos such as are adapted for motor cycles and light cars.

Referring to the accompanying sheets of explanatory drawings Figures 1, 2, and 3 are respectively cross section, longitudinal section and end view (with cover removed) of a combined current generator and ignition coil adapted in accordance with this invention for use in connection with the lighting and ignition system of a motor vehicle.

.Figs. 4; to 6 are diagrams showing alternative systems arranged in accordance with this invention.

Referring to Figs. 13, a shuttle armature a carrying a generator winding 7) is rotatably mounted between the pole shoes 0 of a permanent magnet (Z. 011 one end of the armature is mounted a commutator c of insulating material carrying a pair of conducting segments f. f. One of these (7) is connected by a central pin 9 and metal strip It to one end of the generator winding. The commutator also carries a spring blade 2' in electrical connection with the metal portion of the armature to which is secured the other end of the winding. This blade under centrifugal force when a sufficient speed of rotation is attained. makes electrical connec tion with a stud j on the other segment f. and operates therefore as an electrical out out when the speed falls below a certain value. It will be understood that any other suitable cut-out device may be used. With the armature in the position shown in Figs. 1 and 2, and rotating in the direction of the arrow, (Fig. 3) the segments are situated Specification of Letters Patent. P t ted Apt 19, 1

Application filed March 31, 1920. Serial No. 370,178.

approximately as shown in Fig. 8, and consequently the parts It and iiWOulCl not be in the plane of section of Fig. 2, but for clearness of illustration the said parts have been shown in Fig. 2 as locatedin the plane of section.

The segments f f are respectively connected in turn by a brush is to one end of a battery Z (Figs. 4c, 5 and 6), and by means of a brush is each segment is in turn connectible through a spring contact lever on with the primary winding 0 of the ignition coil and the other end of the battery as here-;

inafter described. In the Fig. 5 arrangement two fixed contacts 72- n: are used in conjunction with the lever m, but in the arrangements shown in the other figures only one fixed contact (at) is used. A condenser is connected to the lever m {LDC contact 02. as is usual in ignition coil interrupters. For convenience in manufacture the iron portion of? the ignition coil (indicated by 0' Figs. 1 and 3) may be the same as that of the generator armature,

which excepting the winding is similar in general construction to the armature of an ordinary ignition magneto. The ignition coil is arranged within the arch of the magnet as shown in Figs. 1 and 2. High tension current can be taken to the engine sparking plug from a terminal g which is connected to one end of the high tension winding 0 of the ignition coil.

The cam 7" for operating the 'lever m is rotated through reduction gear wheels 8, t from the generator armature, the ratio of the wheels being 4t:1 so that the lever m is actuated once in each four revolutions of the armature. As shown in Fig. 3 the cam is of circular form having a gap in its periphery which permits the lever m to close under its spring action on to the contact n. At a certain interval the lever is lifted by the cam to open the said circuit and produce the spark required for ignition.

In Figs. 4:, 5, and 6, for convenience of illustration the cam r is shown arranged to positively close the lever m on to the fixed contact at, but it will be understood from the foregoing that this operation is in practice effected by the spring action of the lever m, the cam serving only to lift the lever m off the contact a.

In Fig. 4 the coil 0 is arranged in series with the generator winding 1) and may serve as an inductance for limiting the current delivered by the generator. As shown the latter is adapted to be periodically short circuited by the lever m. During the short circuit interval current flows through the coil 0 from the battery in the reverse direction to the normal. At the instant of opening the short circuit the current and flux in the coil 0 is suddenly reversed and a high voltage is developed in the secondary winding 0 which is utilized in the production of the ignition spark. In other particulars the diagram is self explanatory. Fig. 5 shows a modification of the scheme shown in Fig. 4. In this arrangement current can be delivered to the battery without passing through the coil 0, by means of the lever m and the extra fixed contact a. When the generator is supplying current to the battery the coil 0 is short circuited by the contact lever m. When the latter short circuits the generator current flows from the battery through the coil 0. On opening the generator circuit and while the lever contacts are midway between the fixed contacts at a, a reversal of current and flux is produced in the coil 0, giving the required ignition spark. Fig. 6 shows a scheme very similar to that of Fig. 5, excepting that the periodic short circuiting of the coil 0 is effected by a gapped or se mental contact piece 1" which rotates with the cam r and has collecting brushes bearing on its periphery, the circuit connections being arranged as shown.

In Figs. 4 6 lamps or-other apparatus in the battery circuit are indicated by 'v.

Having thus described my invention What I claim as new and desire to secure by Letters Patent is 1. In current generating apparatus for use on motor vehicles, the combination comprising a rotary shuttle type current generating armature, a permanent magnet for providing the armature field, an ignition coil, a storagebattery receiving current from the armature, and means for periodically short circuiting the armature and during the short circuit interval permitting current to flow from the battery to the ignition coil,

substantially as described.

2. In current generating apparatus for use on motor vehicles, the combination comprising a rotary shuttle type current generating armature, a permanent magnet for providing the armature field, a high tension ignition coil consisting of primary and secondary windings, a storage battery receiving current from the armature, and means for periodically short circuiting the armature and during the short circuit interval permitting current to flow from the battery to the ignition coil, substantially as described.

'3. In current generating apparatus for use on motor vehicles, the combination comprising a rotary shuttle type current generating armature, an arched permanent magnet for providing the armature field, a high tension ignition coil comprising primary and secondary windings arranged in the arch of the magnet, a storage battery receiving current from the armature, and means for periodically short circuiting the armature and during the short circuit interval permitting current to flow from the battery to the ignition coil, substantially as described. 7

4%. In current generating apparatus for use on motor vehicles, the combination comprising a rotary shuttle type current generating armature, a pair of commutator segments respectively connected to the ends of the armature winding, means for collecting current from said segments, a permanent magnet providing the armature field, an ignition coil comprising primary and secondary windings, a storage battery receiving current from the armature, a movable contact lever and fixed contact arranged to short cir uit the armature and permit current to flow from the battery to the coil when the armature is short circuited, and a cam rotatable by the armature for actuating the lever, substantially as described.

In testimony whereof I have signed my name to this specification.

ERNEST ANSLEY WATSON. 

